The subject of the invention is a trough-like electrolysis cell with horizontally disposed electrodes for manufacturing chlorine from alkali chloride solution by the diaphragm process, in which cell the anodes are attached to the cell cover so that their height can be adjusted.
About 50% of the world electrolysis capacity for manufacturing chlorine consists of electrolysis cells which employ the amalgamation process. The theoretical decomposition voltage for the mercury cell is approximately 3.15 to 3.20 volts. On the other hand, a theoretical decomposition voltage of approximately 2.2 volts is obtained if the alkali chloride electrolysis is carried out in a diaphragm cell with a hydrogen-producing cathode. Consequently, approximately 1 volt can theoretically be saved in cell voltage by the introduction of the diaphragm process, which is of considerable economic importance in times of rising energy costs. In addition to the energy saving, the membrane process offers the advantage of an ecologically harmless process, since no mercury is emitted, and even the lye produced is not contaminated with mercury.
The membrane cell consists of two electrolysis chambers which each have a gas-generating electrode and are separated by a cation-selective membrane. If such a membrane cell were disposed horizontally, a gas cushion consisting of chlorine or hydrogen depending on the arrangement would form underneath the membrane and the resistance of the electrolyte would cancel out the cell voltage advantage.
The object was therefore to create a membrane cell with horizontally disposed electrodes out of the mercury cell, in which membrane cell gas cushions which could affect the electrolyte resistance do not occur.